Résumé
Mammalians have barriers that regulate and limit the distribution of a broad variety of compounds and xenobiotics. Among these, the placental barrier, which forms during embryogenesis, protects the developing fetus. The placenta is composed of several layers of cells acting as a barrier for the diffusion of substances between the maternal and fetal circulatory systems. Lipid-soluble molecules can readily cross while the transfer of large-molecular-weight molecules are limited. Anatomical and functional properties of the placental barrier and similarities to the blood-brain barrier (BBB) will be discussed.